[Bug target/84264] [8 Regression] ICE in rs6000_emit_le_vsx_store, at config/rs6000/rs6000.c:10367 starting with r256656

[bergner at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84264

--- Comment #6 from Peter Bergner <bergner at gcc dot gnu.org> ---
So we end up dropping into rs6000_emit_le_vsx_store from gen_movv4si via:

  if (!BYTES_BIG_ENDIAN
      && VECTOR_MEM_VSX_P (<MODE>mode)
      && !TARGET_P9_VECTOR
      && !gpr_or_gpr_p (operands[0], operands[1])
      && (memory_operand (operands[0], <MODE>mode)
          ^ memory_operand (operands[1], <MODE>mode)))
    {
      rs6000_emit_le_vsx_move (operands[0], operands[1], <MODE>mode);
      DONE;
    }

This is catching the case (during expand) where we have non LE friendly
loads/stores and we need to emit permutes with them.  In the case where we are
ICEing, we actually have a LE friendly Altivec mem:

Breakpoint 9, rs6000_emit_le_vsx_store (dest=0x3fffb580c888,
source=0x3fffb580ea90, mode=E_V4SImode)
    at
/home/bergner/gcc/gcc-fsf-mainline-pr84264/gcc/config/rs6000/rs6000.c:10357
10357   {
(gdb) pr2 dest source
(mem/c:V4SI (and:DI (plus:DI (reg:DI 141)
            (reg:DI 140))
        (const_int -16 [0xfffffffffffffff0])) [1 args+0 S16 A128])
(reg:V4SI 142)

In this case, we can just emit the store normally and don't need to drop into
rs6000_emit_le_vsx_move at all.  Guarding the code above to ensure we don't
have an Altivec mem via altivec_indexed_or_indirect_operand() fixes the ICE:

Index: vector.md
===================================================================
--- vector.md   (revision 258115)
+++ vector.md   (working copy)
@@ -136,8 +136,10 @@ (define_expand "mov<mode>"
       && VECTOR_MEM_VSX_P (<MODE>mode)
       && !TARGET_P9_VECTOR
       && !gpr_or_gpr_p (operands[0], operands[1])
-      && (memory_operand (operands[0], <MODE>mode)
-          ^ memory_operand (operands[1], <MODE>mode)))
+      && ((memory_operand (operands[0], <MODE>mode)
+          && !altivec_indexed_or_indirect_operand(operands[0], <MODE>mode))
+         ^ (memory_operand (operands[1], <MODE>mode)
+            && !altivec_indexed_or_indirect_operand(operands[1],
<MODE>mode))))
     {
       rs6000_emit_le_vsx_move (operands[0], operands[1], <MODE>mode);
       DONE;